Making an API Request

Request URI

Although a request URI is included in the request header, most programming languages or frameworks require the request URI to be passed separately.

A request URI consists of four parts: {URI-scheme} :// {Endpoint} / {resource-path}? {query-string}

For example, to obtain the IAM token in region AP-Singapore, obtain the region's endpoint iam.ap-southeast-3.myhuaweicloud.com and find the resource-path (/v3/auth/tokens) in the URI of the API for obtaining a user token. Then, construct the URI as follows:

https://iam.ap-southeast-3.myhuaweicloud.com/v3/auth/tokens

Figure 1 Example URI

To simplify the URI display in this document, each API is provided only with a resource path and a request method. The URI-scheme of all APIs is HTTPS, and the endpoints of all APIs in the same region are identical.

Request Methods

HTTP defines the following request methods that can be used to send a request to the server.

For example, in the case of the API used to obtain a user token, the request method is POST. The request is as follows:

POST https://iam.ap-southeast-3.myhuaweicloud.com/v3/auth/tokens

Request Header

You can add additional fields, for example, the fields required by a specified URI or HTTP method, to a request header. For example, to request for the authentication information, add Content-Type, which specifies the request body type.

The following table lists the common request header fields.

In addition to supporting token-based authentication, public cloud APIs also support authentication using AK/SK. During AK/SK-based authentication, an SDK is used to sign the request, and the Authorization (signature information) and X-Sdk-Date (time when the request is sent) header fields are automatically added to the request.

For more information, see AK/SK Authentication.

The API used to obtain a user token does not require authentication. Therefore, only the Content-Type field needs to be added to requests for calling the API. An example of such requests is as follows:

POST https://iam.ap-southeast-3.myhuaweicloud.com/v3/auth/tokens
Content-Type: application/json

Request Body

A request body is generally sent in structured format. It corresponds to Content-Type in the request header and transfers content except the request header.

The request body varies according to APIs. Certain APIs do not require the request body, such as GET and DELETE.

In the case of the API used to obtain a user token, the request parameters and parameter description can be obtained from the API request. The following provides an example request with a body included. Replace username, domainname, ********, and xxxxxxxxxx with the actual values. username indicates the username, domainname indicates the account to which the user belongs, ******** indicates the login password, and xxxxxxxxxx indicates the project name, for example, ap-southeast-3. You can obtain the value from Endpoints.

The scope parameter specifies where a token takes effect. You can set scope to an account or a project under an account. In the following example, the token takes effect only for the resources in a specified project. For more information about this API, see Obtaining a User Token Through Password Authentication.

POST https://iam.ap-southeast-3.myhuaweicloud.com/v3/auth/tokens
Content-Type: application/json 

{ 
    "auth": { 
        "identity": { 
            "methods": [ 
                "password" 
            ], 
            "password": { 
                "user": { 
                    "name": "username", 
                    "password": "********", 
                    "domain": { 
                        "name": "domainname" 
                    } 
                } 
            } 
        }, 
        "scope": { 
            "project": { 
                "name": "xxxxxxxx" 
            } 
        } 
    } 
}

If all data required for the API request is available, you can send the request to call the API through curl, Postman, or coding. In the response to the API used to obtain a user token, x-subject-token is the desired user token. This token can then be used to authenticate the calling of other APIs.